I leveled to, and moved the origin to a 10 point plane on a surface I am measuring.

Next, I probed 40 points on the surface and measured the 'Z' location of each point.

Next, I constructed a BFRE plane from the 40 points and measured the flatness of the 40 point plane.

Max Z of the 40 points: 0.0407mm

Min Z of the 40 points: -0.0610mm Range between Max and Min: 0.1017mm

Flatness: 0.0953mm

I was expecting the Flatness output to be the same as the Max-Min range.

Does anyone know why these results are different?

Maybe this is a question for tech support, but I was wondering if someone could email me the math on how flatness is calculated.

PC-Dmis v3.7 MR2

Thanks,

Keith

Next, I probed 40 points on the surface and measured the 'Z' location of each point.

Next, I constructed a BFRE plane from the 40 points and measured the flatness of the 40 point plane.

Max Z of the 40 points: 0.0407mm

Min Z of the 40 points: -0.0610mm Range between Max and Min: 0.1017mm

Flatness: 0.0953mm

I was expecting the Flatness output to be the same as the Max-Min range.

Does anyone know why these results are different?

Maybe this is a question for tech support, but I was wondering if someone could email me the math on how flatness is calculated.

PC-Dmis v3.7 MR2

Thanks,

Keith

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